class LoginResponse {  String tokenType;  int expiresIn;  String accessToken;  String refreshToken;  String openId;  LoginResponse({    this.tokenType,    this.expiresIn,    this.accessToken,    this.refreshToken,    this.openId,  });  LoginResponse.fromJson(Map<String, dynamic> json) {    tokenType = json['token_type'];    expiresIn = json['expires_in'];    accessToken = json['access_token'];    refreshToken = json['refresh_token'];    openId = json['open_id'];  }  Map<String, dynamic> toJson() {    final Map<String, dynamic> data = new Map<String, dynamic>();    data['token_type'] = this.tokenType;    data['expires_in'] = this.expiresIn;    data['access_token'] = this.accessToken;    data['refresh_token'] = this.refreshToken;    data['open_id'] = this.openId;    return data;  }}